Smoke not showing up in render?
For some odd reason the texture coordinates for your voxel texture are undefined: 



Printing the value of the setting with python says that it's set to global, which is not the value you want anyway. Try setting it to generated.

For some reason I also needed to set the viewport maximum draw type to textured in order to get this to work in 2.72, which is extremely odd.. 



This was not needed in 2.69. I've reported this as a bug here. It has been fixed as of this commit, which will be in 2.73.



Also be sure to allow the voxel texture to influence the scattering color of the smoke, otherwise it will not be colored like you might expect: